What is "insulin"?

Insulin, produced by the pancreas, is a vital hormone in the endocrine system that controls the metabolism of carbohydrates, fats, and proteins. It promotes the absorption of glucose from the bloodstream into cells, where it is used for energy or stored for later use. Insulin also helps regulate the storage of excess glucose in the liver and muscles as glycogen. By regulating glucose levels, insulin plays a key role in maintaining stable blood sugar levels and overall energy homeostasis in the body.